Pieces of the comet most likely exploded in Earth’s atmosphere, the researchers suggest,
triggering wildfires across North America. Those fires would have produced enough soot and other compounds to block out the sun and cool the planet. Most scientists think that a similar aboveground explosion, known as an airburst, happened on a far smaller scale in 1908 over Siberia’s Tunguska region. That event produced as much energy as
1,000 Hiroshima bombs (
SN Online: 7/28/09). A similar but even larger cataclysm at the onset of the Younger Dryas, according to the hypothesis’s proponents, would neatly solve several prehistoric puzzles, including what caused the extinctions of large animals and what happened to the Clovis people.
“We have different battles with different disciplines,” he says. He compares these battles to the fights that raged in the 1980s over whether an asteroid struck Earth 66 million years ago, killing off all dinosaurs except birds — an idea that he notes is now widely accepted.
https://www.sciencenews.org/article/younger-dryas-comet-impact-cold-snap
